Automation systems for controlling a technical process or a technical installation usually comprise a control device (PLC), which are integrated in a complex comprising a multiplicity of intelligent electrical devices. Intelligent electronic devices are microprocessor-based devices such as protective and control devices, motor protection devices, intelligent switches and voltage regulators, frequency converters, pressure and temperature measurement transducers, flowmeters and servo drives.
The article “FDI Device Integration—Best of Both Worlds”, atp edition June 2010, pages 16 to 19, discloses the practice of integrating field devices with the FDI concept (Field Device Integration IEC—62769) into an automation installation. The basis for this concept is the provision of information for configuring field devices in a device-specific FDI package. This FDI package comprises a firmly prescribed quantity of information that consists of device definition, business logic, user interface description and user interface plugins. The device definition comprises management information and the device model. The business logic describes the communication logic for the device and is used for ensuring consistency for the device model. The user interface description describes the presentation of the device parameters and device functions. The user interface plugins are programmed components of interface portions for presenting the device parameters and functions.
When field devices are configured by means of EDD (Electronic Device Description) technology IEC 61804, a device manufacturer provides an EDD that contains information about the communication with the device, the business logic and the user interfaces, that is to say what input masks should be presented to a user. By way of example, the business logic includes when what parameters can be written.
FDI technology uses these mechanisms of the EDD and provides the concept of the FDI package, in which, besides an EDD, other information such as a user handbook can be included, but also what are known as UIPs (User Interface Plugins), which provide further user interfaces in other technologies, such as .NET Assemblies, which, in contrast to EDD-based user interfaces, consist of programmed code compiled to form a component.
FDI packages are typically produced by device manufacturers and used by system manufacturers in order to integrate and configure the devices of the device manufacturers in their system.
The EDD may define not only a single user element with various parameters, graphs and other elements but also new windows and dialogs. In this case, a host has certain degrees of freedom and, by way of example, can present a plurality of menus defined in the EDD in different windows simultaneously, or else user interfaces of different device instances.
Furthermore, the EDD specification allows an input context to be defined that contains changes to a device configuration that the user has already made on the interface but has not yet written to the device or the offline configuration.
In such a programming tool, information relating to the devices is visualized and functions such as parameterization operations are performed. To this end, the user first needs to select a device from a multiplicity of devices.
Field devices are described using EDD files. This EDD is used to provide both the device-specific information relating to the communication with the field device via a field bus and all the elements for configuration and for monitoring of the field device by means of an appropriate user interface. In this case, the EDD defines logic that needs to be able to be implemented for every change in a single device parameter.
In a client/server architecture such as in FDI, the EDD is processed on the server, and the user interface itself is provided on a client in this case. For the purpose of configuring a field device, an appropriate user interface is activated on the server for every change in a value in accordance with the processing logic defined in the EDD. This necessitates intensive interaction between the client and the server for every change in a parameter in the parameterization interface. During the editing process, the content to be presented and altered values additionally need to be repeatedly transmitted from the portion processing EDD to the user interface.
In a system having a large number of field devices and clients, this results in bottlenecks in the client/server communication and hence in user interfaces whose reaction response over time no longer meets the usual requirements.